Sometimes I spend a couple of weeks at a time without access to Wi-Fi, & I'd love to be able to update my iCloud backup manually without having to find a Wi-Fi network.

Also, I'd love it if Apple increased the download limit on iTunes/Podcasts/App Store from 50MB to 100MB.
I watch a lot of video podcasts, & I can afford to download them with my 3GB monthly data allowance.